Add + operator for Deterministic::Result class
Merge pull request #17 from jsliwinski/plus_operator_for_result_monad

Add + operator for Deterministic::Result class
Bump version to v0.14.0
Remove space in lambda expression revert support for ruby 1.9.3
Merge pull request #18 from jsliwinski/bugfix/lambda_ruby_1_9_3

Remove space in lambda expression revert support for ruby 1.9.3
Bump version to v0.14.1
Merge branch 'master' of github.com:pzol/deterministic
Update README for enums
Bump version to v0.15.0
Rewrite all using enums